The invention relates to a force-applying device for a brake.
A conventional force-applying device of the general type under consideration is described in International Patent Application WO 01/44677 A1. In the known force-applying device described in WO 01/44677 A1, the friction elements of a brake are clamped via a lever. A power generator acting at a variable point of the lever and provided with a preloaded spring can exert an adjustable force on the lever and thus on the brake linings by varying the power point. The operating position of this power generator can be adjusted via a servo motor, such as an electric motor. The advantage of this construction is that the power drawn by the electric motor is considerably smaller than in the case of brake application directly by the electric motor, while at the same time brake application takes place relatively rapidly and consequently the energy needed per braking action is also smaller. The major part of the energy needed to achieve brake release and the associated reloading of the spring of the power generator is then obtained from the energy stored in the brake linings and further parts of the brake as a result of elastic deformation.
The known force-applying device described in WO 01/44677 A1 already has high efficiency in terms of power draw and energy consumption, and it exhibits a favorable brake-application characteristic. The basic object of the present invention is to provide, for a brake, an alternative force-applying device that also permits considerable reduction of the power and energy demand compared with direct clamping devices.
The invention has the advantage that safe and reliable functioning of the force-applying device is guaranteed in a wide range of operating angles.